Dear debabratanag99,
I have already given you the answer, that scattering effect is for particles smaller in size than the wavelength. The wavelength of light is approximately from 3500 A to 7500 A. Theoretical models suggest that the average cluster may encompass as many as 90 H2O molecules at 0°C, so that very cold water can be thought of as a collection of ever-changing ice-like structures. Therefore there is no point in discussing about scattering.
This explanation is flawed for more than one reason. Fog droplets are, on
average, smaller than cloud droplets, but they still are huge compared with
the wavelengths of visible light. Thus scattering of such light by fog is
essentially wavelength independent. Unfortunately, many people learn
(without caveats) Rayleigh's scattering law and then assume that it applies
to everything. They did not learn that this law is limited to scatterers
small compared with the wavelength and at wavelengths far from strong
absorption.